Phenylcarboxamides are a kind of novel insecticides with high efficacy and safety. 3-Bromo-N-(4-chloro-2-methyl-6-(methylcarbamoyl)phenyl)-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxamide is highly effective against insects, which is commercialized by DuPont, its generic common name is chlorantraniliprole; 3-Bromo-1-(3-chloropyridin-2-yl)-N-(4-cyano-2-methyl-6-(methylcarbamoyl)phenyl)-1H-pyrazole-5-carboxamide in development is highly effective against insects too, whose common name is cyantraniliprole.

There are a number of methods reported for preparing phenylcarboxamides, for example:
WO03/015519 A1 discloses that 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxylic acids reacts with substituted anthranilic acids, in the presence of methanesulfonyl chloride and pyridine as acid binding agent to give the benzoxazinones in 86%-92% yield. Then the product reacts with the alkylamine to yield the phenylcarboxamides. Calculated by 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxylic acids, the total yield of the two-steps is 58%-65%. Bioorganic & Medicinal Chemistry Letters, 17 (2007), 6274-6279 discloses that 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl chlorides react with isatoic anhydrides to give the benzoxazinones in 23% yield.
WO2006/062978A1 discloses that 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxylic acids react with substituted aminobenzamid, in the presence of methanesulfonyl chloride and 3-aminepyridine as acid binding agent to give the phenylcarboxamides and the dehydrated-cyclization by-product, which can be converted into the target phenylcarboxamides under the reaction with hydrochloric acid. Calculated by 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxylic acid, the crude yield under the best reaction conditions is 99.5% without mention of the product purity. The total yield is 88.4% after purified by recrystallization.
The methods for preparing 3-halo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylates and 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl chlorides have been disclosed by Bioorg. Med. Chem. Lett. 17 (2007), 6274-6279, WO03/015519 A1, and CN101298451. The 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxylates can be prepared by the oxidation of 3-halo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylates. They are hydrolyzed, and acyl chlorination into 3-halo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl chlorides. The total yield of three-steps is 70%.
The researchers continuously make efforts to research and develop more advanced and favourable, and more environmentally friendly novel preparation methods, so as to manufacture the highly effective and safe phenylcarboxamide insecticides with higher quality and lower cost.